Digital Commons Network^™

Rheological Study Of Polymer Flow Past Rough Surfaces With Slip Boundary Conditions, Anoosheh Niavarani, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The slip phenomena in thin polymer films confined by either flat or periodically corrugated surfaces are investigated by molecular dynamics and continuum simulations. For atomically flat surfaces and weak wall-fluid interactions, the shear rate dependence of the slip length has a distinct local minimum which is followed by a rapid increase at higher shear rates. For corrugated surfaces with wavelength larger than the radius of gyration of polymer chains, the effective slip length decays monotonically with increasing corrugation amplitude. At small amplitudes, this decay is reproduced accurately by the numerical solution of the Stokes equation with constant and rate-dependent local …

Newsletters For The Larsen Tractor Museum, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

No abstract provided.

Engineering@Nebraska - Fall 2008

Engineering@Nebraska (Alumni Magazine)

Table of Contents:

Front & Center
A Welcome Home: Zero Net Energy Test House unites university and industry as students' learning is caught green-handed
Making their mark on mars: Huskers at Honeybee, a New York City robotics firm, work on Mars missions
Epigenetics: A dialogue between biologists and engineers: Joe Turner, professor and chair of the Department of Engineering Mechanics, collaborates with UNL plant scientist Sally McKenzie on nanoscale work with huge potential
Energy monitoring on the home front: Together with OPPD, Nebraska Engineering studies devices to promote efficiency
Wave of the future: Biological Systems Engineering professor Greg Bashford creates …

Effects Of Lline Rate On Vvideo Qos Over Wireless Networks: An Experimental Approach, Stuart Wallace, Mark Davis

Conference papers

Video streaming over Wireless Local Area Networks (WLANS) is becoming an increasingly popular service. However, end user OoS is highly influenced by many factors. These include the video codec used, the packetization scheme, error concealment and correction techniques, the complexity of the video, propagation losses, and the line rate. In this paper the effect of the line rate on the capacity of the network when streaming multimedia content is analyzed experimentally. It is shown that as the line rate decreases the bandwidth load of the video stream dramatically increases leading to poor QoS at the client side. As automatic line …

Cs 205-08: Introduction To Computers And Office Productivity Software, Kim Gros

Computer Science & Engineering Syllabi

Focus on learning MS Office software applications including word processing (intermediate), spreadsheets, database and presentation graphics using a case study approach where critical thinking and problem solving skills are required. Computer concepts are integrated throughout the course to provide an understanding of the basics of computing, the latest technological advances and how they are used in industry. Ethics and issues encountered in business are discussed to challenge students on societal impact of technology.

Cs 205: Computer Literacy And Office Automation, Ann Tirpack

Computer Science & Engineering Syllabi

No abstract provided.

Chain-Type Wireless Sensor Network For Monitoring Long Range Infrastructures: Architecture And Protocols, Chang Wen Chen, Yu Wang

Electrical Engineering and Computer Science Faculty Publications

We present in this paper an investigation of a special class of wireless sensor networks for monitoring critical infrastructures that may extend for hundreds of miles in distances. Such networks are fundamentally different from traditional sensor networks in that the sensor nodes in this class of networks are deployed along narrowly elongated geographical areas and form a chain-type topology. Based on careful analysis of existing sensor network architectures, we first demonstrate the need to develop new architecture and networking protocols to match the unique topology of chain-type sensor networks. We then propose hierarchical network architecture that consists of clusters of …

Education Enhancement Using Visualization And Simulation Tools For Basic Circuit Theory Concepts, Jariwala Rajvi Prakashchandra

Electrical & Computer Engineering Theses & Dissertations

New generation web-technologies and supporting development tools have prompted opportunities for developing new methods of teaching and learning. Web-based visualization and simulation modules developed for ODU's ECE201 Circuit Theory course are presented in this thesis. Visualization and simulation methodology is used to make learning process more interactive and effective. Macromedia FLASH software, which has the extensive graphical animation capabilities, is used to develop visualization modules. Lab VIEW is a leading graphical development tool for science and engineering with a built-in functionality for simulation, data acquisition, instrument control, measurement analysis and data presentation. These capabilities are utilized to develop web-based simulation …

Virtualization Of Physical Experiments Using Real-Time Data Generation From A Computational Fluid Dynamics Code, Kaustubh A. Dharwadkar

Mechanical & Aerospace Engineering Theses & Dissertations

This work presents a methodology for mapping physical experiments into real-time, web-based virtual experiments. The four broad elements included in the physical-to-virtual experiment transformation methodology are: (a) computer solution of conservation equations of mass and momentum to generate velocity and pressure (virtual) data that serve as the foundation for recreating the physical phenomenon in the virtual domain; (b) use of virtual pressure and velocity sensing devices to generate signals or readings from computed virtual data that can be observed and read on a computer screen; (c) use of visualization software such as Macromedia FLASH to create a highly interactive environment …

Parameter Estimation Of The Arterial System, James Charles Carter Ii

Mechanical & Aerospace Engineering Theses & Dissertations

There are a number of disorders that originate from or involve faulty operation of the cardiovascular system. Diseases such as atherosclerosis, diabetes and hypertension can have a debilitating effect on blood flow. This makes the tools for simulating the effects of such diseases on blood flow important. Measures, such as pulse wave velocity, that are generated by models of the cardiovascular system can be important indicators of cardiac health. Although physically measurable, obtaining some parameters comes with a high cost and discomfort to the patient. Models can provide an assessment of many important parameters. The purpose of this project was …

Sequestration And Ultrasound-Induced Release Of Doxorubicin From Stabilized Pluronic P105 Micelles, John D. Pruitt, William G. Pitt

Faculty Publications

Controlled drug delivery from micelles requires that the micelles remain stable when diluted below their critical micelle concentration, such as upon injection into blood. A cross-linked, interpenetrating network of N,N-diethylacrylamide (NNDEA) was polymerized in the core of Pluronic P105 micelles to stabilize temporarily the micelles at concentrations below the critical micellar concentration of free P105. The stabilized Pluronic micelles (called Plurogels) were able to sequester the drug doxorubicin (Dox) and protect HL-60 cells from the drug at concentrations where non-stabilized Pluronic provided no protection. The protection lasted ~ 12 hr, which is similar to the half-life of the particles. Application …

Fatigue Testing Of Three Peristernal Median Sternotomy Closure Techniques, Cameron Wangsgard, David J. Cohen, Lanny V. Griffin

Biomedical Engineering

Failure of a sternotomy closure because of closure system fatigue is a complication that may result in dehiscence and put the individual at risk for serious complications. The purpose of this study was to assess the fatigue performance of three peristernal median sternotomy closure techniques (figure-of-eight stainless-steel wires, figure-of-eight stainless-steel cables, or Pectofix Dynamic Sternal Fixation [DSF] stainless-steel plates) in order to quantify the potential risk of fatigue failure of these devices when subject to cyclic loads in physiologically relevant loading directions.

Response To Changes In Key Stimuli Through The Co-Evolution Of Sensor Morphology And Control, Gary Parker, Pramod J. Nathan

Computer Science Faculty Publications

Co-evolving a robot’s sensor morphology and control program increases the potential that it can effectively complete its tasks and provides a means for adapting to changes in the environment. In previous work, we presented a learning system where the angle, range, and type of sensors on a hexapod robot, along with the control program, were evolved. Although three sensor stimuli were detectable by the system, it used only two due to the relative importance of these two stimuli in completing the task. In the research presented in this paper, we used the same system, but reduced the availability of a …

Cryptosporidium Outbreak (Water Treatment Failure): North Battleford, Saskatchewan, Spring 2001, Patrick B. Jameson, Yung-Tse Hung, Chin Y. Kuo, Paul A. Bosela

Civil and Environmental Engineering Faculty Publications

An outbreak of cryptosporidiosis occurred in the town of North Battleford, Saskatchewan, Canada in the spring of 2001. The outbreak left thousands of people sick including about 50 people hospitalized. The source of the outbreak was from the city's surface water treatment plant. The Sedimentation Contact Unit did not satisfactorily remove suspended solids from the source water, resulting in filter breakthrough. Contaminated water was released into the distribution system causing the outbreak. Communication breakdown and confusion exacerbated the situation, extending the duration of the outbreak. The outbreak prompted the province to change the way it regulated municipal utilities of water …

Modeling And Parameter Estimation Of Spacecraft Lateral Fuel Slosh, Yadira Rodriguez Chatman

Master's Theses - Daytona Beach

Predicting the effect of fuel slosh on spacecraft and launch vehicle attitude control systems has been a very important and challenging task and has been the subject of considerable research over the past years. Analytic determination of the slosh analog parameters has been met with mixed success and is made more difficult by the introduction of propellant management devices such as elastomeric diaphragms. The experimental set-up in this research incorporates a diaphragm in a simulated spacecraft fuel tank subjected to lateral slosh behavior. This research focuses on the parameter estimation of a SimMechanics model of the simulated spacecraft propellant tank …

A Comparative Analysis Of Greenroof Designs Including Depth Of Media, Drainage Layer Materials, And Pollution Control Mediaa, Martin Wanielista, Michael Hardin

BMP Trains Research and Publications

No abstract provided.

Assessment Of The Effects Of Increasing Levels Of Physiological Realism In The Computational Fluid Dynamics Analyses Of Implanted Coronary Stents, Jonathan Murphy, Fergal Boyle

Conference Papers

Coronary stent implantation can improve blood flow in an artery that has been narrowed by the build up of arterial plaque. However, the implantation of the stent will change the geometry of the vessel wall. The haemodynamic effects of the stents presence and alteration of the vessel wall are unclear. The redistribution of flow induced vessel wall shear stress (WSS) and wall shear stress gradient (WSSG) may directly contribute to restenosis (re-blockage). Computational fluid dynamics (CFD) is used extensively to identify these parameters in stented vessels. However, simplifications to the model of the stented artery are common. In this paper, …

Pervasive Open Spaces: An Intelligent And Scalable Pervasive Environment For Providing Contextual Resource Sharing, Amgad Magdy Madkour

Archived Theses and Dissertations

No abstract provided.

Low-Flow Perfusion Of Guinea Pig Isolated Hearts With 26°C Air-Saturated Lifor Solution For 20 Hours Preserves Function And Metabolism, David F. Stowe, Amadou K.S. Camara, James S. Heisner, Mohammed Aldakkak, David R. Harder

Biomedical Engineering Faculty Research and Publications

Background

Donor human hearts cannot be preserved for >5 hours between explantation and recipient implantation. A better approach is needed to preserve transplantable hearts for longer periods, ideally at ambient conditions for transport. We tested whether Lifor solution could satisfactorily preserve guinea pig isolated hearts perfused at low flow with no added oxygen at room temperature for 20 hours.

Methods

Hearts were isolated from 18 guinea pigs and perfused initially with oxygenated Krebs–Ringer (KR) solution at 37°C. Hearts were then perfused with recirculated Lifor or cardioplegia (CP) solution (K⁺ 15 mmol/liter) equilibrated with room air at 20% of control …

Enhanced Na+/H+ Exchange During Ischemia And Reperfusion Impairs Mitochondrial Bioenergetics And Myocardial Function, Mohammed Aldakkak, David F. Stowe, James S. Heisner, Marisha Spence, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

Inhibition of Na+/H+ exchange (NHE) during ischemia reduces cardiac injury due to reduced reverse mode Na+/Ca2+ exchange. We hypothesized that activating NHE-1 at buffer pH 8 during ischemia increases mitochondrial oxidation, Ca2+ overload, and reactive O2 species (ROS) levels and worsens functional recovery in isolated hearts and that NHE inhibition reverses these effects. Guinea pig hearts were perfused with buffer at pH 7.4 (control) or pH 8 +/- NHE inhibitor eniporide for 10 minutes before and for 10 minutes after 35- minute ischemia and then for 110 minutes with pH 7.4 buffer alone. Mitochondrial NADH and FAD, [Ca2+], and superoxide …

Human Swarm Interaction For Radiation Source Search And Localization, Shishir Bashyal, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This study shows that appropriate human interaction can benefit a swarm of robots to achieve goals more efficiently. A set of desirable features for human swarm interaction is identified based on the principles of swarm robotics. Human swarm interaction architecture is then proposed that has all of the desirable features. A swarm simulation environment is created that allows simulating a swarm behavior in an indoor environment. The swarm behavior and the results of user interaction are studied by considering radiation source search and localization application of the swarm. Particle swarm optimization algorithm is slightly modified to enable the swarm to …

Bs News

Building Services Engineering

No abstract provided.

Enhancing Water Removal From Whole Stillage By Enzyme Addition During Fermentation, Ana Beatriz Henriques, David B. Johnston, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Removal of Water from Coproducts in the Fuel Ethanol Process Requires a Significant Energy Input. in This Study, the Addition of Commercially Available Cell-Wall-Degrading Enzymes Was Investigated to Determine Whether or Not the Enzymes Could Reduce the Amount of Water Bound within the Wet Grains. This Would Have the Effect of Allowing More Water to Be Removed during Centrifugation, Reducing the Time and Energy Needed during the Drying Process. the Experiment Screened 15 Cell-Wall-Degrading Enzyme Preparations. a Significant Reduction in Water-Binding Capacity Was Found for a Number of Enzymes Tested in the Initial Screening. the Experiment Was Repeated and …

Bio-Inspired Algorithms For The Design Of Multiple Optimal Power System Stabilizers: Sppso And Bfa, Tridib Kumar Das, Ganesh K. Venayagamoorthy, Usman O. Aliyu

Electrical and Computer Engineering Faculty Research & Creative Works

Damping intra-area and interarea oscillations are critical to optimal power flow and stability in a power system. Power system stabilizers (PSSs) are effective damping devices, as they provide auxiliary control signals to the excitation systems of generators. The proper selection of PSS parameters to accommodate variations in the power system dynamics is important and is a challenging task particularly when several PSSs are involved. Two classical bio-inspired algorithms, which are smallpopulation- based particle swarm optimization (SPPSO) and bacterial foraging algorithm (BFA), are presented in this paper for the simultaneous design of multiple optimal PSSs in two power systems. A classical …

Combat Identification Using Multiple Tuav Swarm, Younin Kang

Theses and Dissertations

In modern warfare, Tactical Unmanned Aerial Vehicles (TUAVs) are rapidly taking on a leading role in traditional and non-traditional ISR, to include Automatic Target Recognition (ATR). However, additional advancements in processors and sensors on TUAVs are still needed before they can be widely employed as a primary source for positive identification in the Combat Identification (CID) process. Cost is a driving factor for operating an ATR system using multiple TUAVs. The cost of high quality sensors appropriate for a single TUAV can be significantly higher than less sophisticated sensors suitable for deployment on a group, or swarm, of coordinated TUAVs. …

Experimental Investigation Of The Effect Of Sonication On The Precipitation Of Grieseofluvin By Impinging Jets, Ankit H. Patel

Theses

Almost 80% of drugs on the market are manufactured as solid dosage forms, such as tablets. Drug bioavailability increases as the particle size decreases and the surface area per unit volume of drug increases. Therefore, there is a keen interest by the pharmaceutical industry to develop techniques that can be used to manufacture particles of active pharmaceutical ingredients (API) in the nano/micro particle range. Impinging jets is one of the most promising techniques to do so.

In this work, a submerged impinging jet system coupled with an ultrasonic probe (sonicator) was used to precipitate Griseofulvin, a common, poorly water-soluble antifungal …

Design And Fabrication Of A Microneedle For The Implantation Of Floating Microstimulators, Faysal Ahmed

Theses

Neural prosthetics are used to stimulate any remaining functional nervous tissue in order to restore function in visual, auditory, or other physiological components associated with the nervous system. Microelectrodes have been used in stimulating and detecting electrical activity in neurons. When stimulating or recording neural tissue activity using microelectrodes, there are usually many problems and difficulties in obtaining the correct functionality and results. There is great difficulty in placing these microelectrodes in a specific location in the central nervous system due to various problems with the methodology used. Many different techniques such as the traditional interconnected microelectrodes have been an …

Research On Logistic Management In Deltai Medical Company, Yan Hu

World Maritime University Dissertations

No abstract provided.

Interoperability Measurement, Thomas C. Ford

Theses and Dissertations

This research presents an inaugural general method of measuring the collaborative and confrontational interoperability of a heterogeneous set of systems in the context of an operational process. The method is holistic, fundamental, flexible, and mathematical in nature and accommodates all types of systems and interoperations. The method relates the interoperability measurement to measures of operational effectiveness for confrontational operational processes. Extant leveling methods of describing interoperability are shown to be a special case of the more general method given in this research and the general interoperability measurement method is demonstrated through the presentation of coalition interoperability, suppression of enemy air …

Engineered Micro-Environments And Vibrational Culture Systems For Vocal Fold Tissue Engineering, Jaishankar Kutty

All Dissertations

Voice is produced by the conversion of aerodynamic energy from exhalation to acoustical energy for voice production by the vocal folds (membranous connective tissue) located in the larynx. The quality of voice depends on the biomechanical properties of the multi-layered vocal fold tissue which derive from its extracellular matrix (ECM) organization and composition. The wound healing response to vocal fold injuries is characterized by scarring and subsequent dysphonia due to alterations in the biomechanical properties of the tissue.
The work presented here is motivated by the importance of voice in maintaining quality of life and the inability of current treatment …